Electronic shelf labels are becoming a popular and intelligent way to display product information on a shelf. The customer benefits by having all the information they need about the product, and the retailer benefits by having programmable information that can be readily changed by various electronic means. For example, prices can be kept up to date without printing new price changes. More permanent information can be printed on another portion of the electronic shelf label, such as a removable or permanent overlay that allows the electronic display to show through.
Exemplary electronic shelf labels as discussed above are shown and described in U.S. Pat. No. 5,111,196 issued to Hunt, U.S. Pat. No. 5,619,416 issued to Kosarew, U.S. Pat. No. 6,217,966 issued to Finster et al., and U.S. Pat. No. 6,552,663 issued to Swartzel et al. These patents describe electronic shelf labels that include a liquid crystal display, a mounting support, onboard electronics, a printable overlay, and a power source to provide viewability of the display at all times. One problem with the aforementioned devices is the need of a continuous power source and replacement of said power source on a regular basis. Without the power source, the display is blank.
To overcome the above problem, a bistable liquid crystal display that retains written information on the display in the absence of power can be used. One such electronic shelf label is shown and described in U.S. Pats. Nos. 5,751,257 and 6,253,190, both issued to Sutherland, which describe a system including an electronic shelf label having a bistable liquid crystal display for displaying price data and a Universal Product Code (“UPC”) bar code, wherein the information programmed in the display remains on the display in the absence of power. The shelf label has a set of synchronizing indicators and corresponding electrical contacts on the front side of the display, which are capable of interacting with a hand-held device that is connected to a central computer that contains inventory and price information. The hand held device can be used to read the UPC bar code on the shelf label and update or write corresponding price information on the label. Both the UPC and the price information are shown on the display.
Including the UPC as a writable element on the shelf label significantly increases the complexity and cost of the shelf label. The resolution needed to produce UPC information requires 113 modules of data, and therefore a corresponding number of contacts on the front of the display. The UPC for a product typically does not change over the life of the product. Other static information, for example, a human readable description of the product, a unit identification (e.g. per oz. or per 100 sheets), or the like, can also be desirable on the display. The placement of static information such as the UPC in writable form on the shelf label unnecessarily complicates the display structure of the label.
One solution to the aforementioned problem is shown and described in U.S. Pat. No. 6,637,650 issued to Capurso et al. It describes an electronic shelf label including a bistable liquid crystal display, which displays information even in the absence of power. A printable overlay containing the bistable liquid display is provided on a printable overlay sheet. The retailer can print static information on the overlay sheet, peel off the overlay containing the display, and attach it to a support. The support provides electrical continuity to the display by way of conductive adhesive and embedded conductive strips. Once attached to the conductive adhesive, the embedded conductive strips in the support provide a front contact outside the overlay area for electronic interfacing in order to change the information on the display. However, careful alignment of the overlay with the embedded conductive strips in the support is required to provide power to the display. Further, because the display is part of the overlay, and is not powered as provided to the retailer, it is difficult to test the functionality of the display before assembly with the support.
There is a need for a shelf label having a conductively mounted display wherein the functionality of a support for the display and the display can be tested prior to reaching the retailer, and wherein static information can be provided separately from the display, for example, on an overlay.